She took twice the prescribed dose of sleeping tablets.

她服用了所开剂量两倍的安眠药。

《柯林斯英汉双解大词典》

I take sleeping tablets only once a week because they are addictive - three times the recommended dose (with my GP's blessing) to ensure three to four hours' solid sleep.

我每周服用一次安眠药，因为那是会上瘾的药物，但用量却是处方的三倍，这样可以保证我有三到四个小时安稳的睡眠。

youdao

Taking a lethal dose of sleeping pills is not allowed in any case.

任何情况下都不允许服用致死剂量的安眠药片。

youdao

Once in her own room, she would take sleeping pills, occasionally a double dose a game that she played against herself, sinking almost too far into sleep.

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